1. Field
The following description relates to a rechargeable battery, and more particularly to a rechargeable battery having a safety apparatus that can prevent or reduce the chance of an explosion when a rechargeable battery is overcharged.
2. Description of the Related Art
Unlike a primary battery that is not designed to be recharged, a rechargeable battery can be repeatedly charged and discharged. Low-capacity rechargeable batteries are used for portable compact electronic apparatuses such as mobile phones, notebook computers, and camcorders, and high-capacity rechargeable batteries are widely used as a power source for driving a motor of a hybrid vehicle, etc.
A high-output rechargeable battery using a non-aqueous electrolyte having high energy density has been recently developed. The high-output rechargeable battery is configured to have high capacity by connecting a plurality of rechargeable cells in series so that it can be used for driving a motor for an apparatus requiring a large amount of power, i.e., an electrical vehicle, etc.
One large-capacity rechargeable battery is commonly formed with a plurality of rechargeable batteries coupled in series. The rechargeable battery may, have a cylindrical shape or prismatic shape.
The prismatic rechargeable battery includes an electrode assembly that has a positive electrode and a negative electrode with a separator interposed therebetween, a case having a space for containing the electrode assembly, a cap plate that seals the case and has a terminal hole into which an electrode terminal is inserted, and an electrode terminal that is electrically connected with the electrode assembly and is inserted into the terminal hole of the cap plate, the terminal protruding out of the case.
When excessive heat is generated inside the rechargeable battery or internal pressure is increased due to dissolution of an electrolyte solution, the battery may explode or combust. Particularly, in the case of the prismatic battery, due to the characteristics of its terminal structure, it is difficult to have a structure that cuts off or discharges current when heat and pressure are increased, especially when compared to the cylindrical battery.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.